Sometimes people lie so often that you will never be able to trust them again.

I'd never trust a guy who signs secret kill lists, even targeting US citizens without having a trial. He even publicly joked about this, which is sign of insanity to me.

And then there's the case of a jailed journalist from Jemen (who reported about a drone bombardment in Jemen), where he personally called the president of Jemen to prevent him from releasing the journalist.

http://en.wikipedia.org/wiki/Abdulelah_Haider_Shaye